JPH0595898A - Tool inserting channel of endoscope - Google Patents

Abstract

PURPOSE:To prevent deformation or buckling of a joint part with the foremast part by interposing a netting with certain necessary places spot welded between urethane layers, forming thereby an outer layer, and placing this outer layer over the inner layer of a flexible tube in an angle part at the foremost of a channel for insertion of a processing tool. CONSTITUTION:A flexible tube 7 consisting of an inner layer 11 and an outer layer 12 is inserted inside of an angle part at the foremost of a processing tool inserting channel in an endoscope. The foremost of this flexible tube 7 is connected with the foremost hard part through a coupling pipe. The outer layer 12 is configured with urethane layers differently long in the axial direction and a netting 14 which consists in a braid of metal fibers and is interposed between the urethane layers. The spot welded part S of the netting 14 is made denser toward the foremost and coarser gradually toward the tail so that the compliance with the bending stress is incremental toward the tail. This prevents deformation or buckling of the joining point with the foremost hard part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a treatment instrument insertion channel for inserting a treatment instrument such as forceps in an endoscope used for medical purposes.

[0002]

2. Description of the Related Art Endoscopes are generally used to diagnose upper and lower gastrointestinal tracts and organs, and to collect cells in the body.
It is used to perform operations such as hemostasis and removal of polybes, and other treatments. For this reason, the endoscope has an operation unit for an operator such as a doctor to hold and operate,
It is composed of an insertion part to be inserted into the patient's body, and a connector part to be connected to a light source for illuminating the inside of the patient and a device having an air / water supply function. The operation unit is provided with an angle mechanism for controlling the distal end of the insertion unit to guide it to a target site in the body and an inlet for a forceps or other treatment tool. In the insertion part, an image pickup means, a cable connected to the image pickup means, a light guide fiber for internal illumination, a treatment instrument insertion channel for guiding the treatment instrument,
Wires and the like are installed to control the bending operation of the air supply and water supply channel and the bending operation of the angle part that constitutes the part near the tip of the insertion part by remote control. Also, in the connector part,
It incorporates a light guide fiber, an air / water supply tube, and a cable.

Of the above-mentioned constructions, the treatment instrument insertion channel having an inner diameter of about 1 mm to 5 mm is used according to the purpose, and a typical condition that the treatment instrument insertion channel must have is the typical condition. There are the following items. First of all, it must be flexible so that when the insert bends, it follows and bends. In particular, since the curved portion of the insertion portion is curved with an extremely small radius of curvature, it can be easily bent at least in the curved portion of the treatment instrument insertion channel, and when the bending is released, it can be reliably performed. Must be adapted to restore. Next, since the treatment instrument is inserted into the treatment instrument insertion channel, at least the inner surface of the treatment instrument insertion channel must be slippery in order to smoothly guide the treatment instrument.
Furthermore, since the endoscope is, by its nature, washed every time it is used, it must be chemically resistant. In short, the treatment instrument insertion channel has airtightness,
Watertightness, flexibility, kink resistance, shape retention, slipperiness,
Chemical resistance and cleaning / disinfecting properties are required.

The structure of the tube used as the treatment instrument insertion channel requiring the above characteristics is as follows:
A structure in which a net formed by braiding metal fibers in a polymer material such as synthetic resin or rubber is embedded is disclosed in, for example, Japanese Patent Laid-Open No. 59-151933. By configuring in this manner, the treatment instrument has bendability and resilience when the bend is released, and the member forming the inner layer and the member forming the outer layer are appropriately matched to the request, thereby providing a treatment instrument. Improves slipperiness, airtightness, watertightness, chemical resistance, etc. when inserting. Moreover, since the net improves the strength, kink resistance, shape retention, etc. are also improved.

Here, the insertion portion of the endoscope is
It can be divided into a soft part, an angle part and a hard tip part. The flexible part occupies most of the part connected to the operating part, the angle part is connected to the tip part of the flexible part, and the hard tip part is connected to the tip side of the angle part. Here, the angle portion is designed to be curved in any direction in order to direct the tip hard portion in a desired direction.
For this reason, wires for controlling the bending operation of the angle portion by remote operation are provided at the vertical and horizontal positions.
When the four wires are push-pulled from the operation section by remote control, the angle section bends in the vertical and horizontal directions. The above-mentioned treatment instrument insertion channel is also inserted into this angle portion, and its tip portion is connected to a connecting pipe attached to the tip rigid portion, and this tip communicates with the treatment instrument insertion passage formed in the tip rigid portion. The treatment instrument insertion passage is opened as a treatment instrument lead-out port at the end surface portion or the side surface portion of the hard tip portion.

[0006]

By the way, when the angle portion is operated and bent, the treatment instrument insertion channel also located in the angle portion bends following the treatment instrument insertion channel. Since the distal end portion is connected to the connecting pipe that is a hard member, the hardness changes abruptly from the flexible treatment instrument insertion channel to the hard connecting pipe. Moreover, in this angle portion, not only simple bending in the vertical direction and the horizontal direction, but also a combined operation of bending in the horizontal direction in a state of being bent in the vertical direction may be performed. Twist will be added to the treatment instrument insertion channel. Therefore, the distal end hard portion of the treatment instrument insertion channel,
That is, there is a high possibility that the connecting portion to the hard pipe or a portion in the vicinity thereof will be buckled or deformed.

The present invention has been made in order to solve the problems of the prior art as described above, and an object of the present invention is to provide at least a continuous portion of the treatment instrument insertion channel to the distal end hard portion. The purpose is to ensure protection without buckling or deformation.

[0008]

In order to achieve the above-mentioned object, the present invention provides a metal fiber in a tube made of a polymer material, which is provided so as to be located at least in an angle portion of an insertion portion of an endoscope. It has a flexible tube in which a braided net is embedded, and a plurality of spot welds are formed at a portion near the end portion of the insertion portion on the connection portion side to the distal end hard portion of the insertion portion in the net. It is a feature.

[0009]

In the flexible tube forming the treatment instrument insertion channel, a net is embedded in order to maintain kink resistance and shape retention without sacrificing flexibility. The net is made of metal fiber. The wire is braided with a predetermined number and striking number. When the wires intersecting each other are fixed, the stretchability of the net is restricted, and the part becomes hard. .. In view of this, the net is fixed by spot welding the strands that intersect each other at a plurality of positions in the length direction from the end portion on the side of the continuous portion to the hard tip portion. Also, in order to obtain uniform hardness in all directions, weld at multiple points in the circumferential direction, at least three points (however, if the bending direction of the angle part is only the up, down, left or right direction). Can be welded at two points). As a result, the vicinity of the connection to the distal end hard portion of the treatment instrument insertion channel becomes harder and the hardness does not change rapidly, and spot welding improves the strength of the relevant portion. It is possible to prevent inconvenience such as deformation.

Here, it is preferable that the change in hardness described above be continuous from the distal end portion of the flexible tube forming the treatment instrument insertion channel. For this,
It suffices to make the spot-welded portion in the length direction the densest on the tip side and change the welding pitch interval so that it becomes coarse gradually. Further, of the treatment instrument insertion channel, a flexible tube with a net embedded therein is provided in the entire angle portion and up to a position where it enters the flexible portion, and most of the flexible portion is formed of a tube without a net. There is also a structure in which the two tubes are connected by using a connecting pipe or the like, but in this case, the same applies to the end of the flexible tube on the side of connection to the tube on the soft side. Spot welding can be performed.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. First, FIG. 1 shows a cross section in the vicinity of the distal end portion of the insertion portion of the endoscope. In the figure, built-in components other than the treatment instrument insertion channel, that is, a light guide, an image guide (in the case of an electronic endoscope, a signal cable provided in place of the image guide), an air / water pipe, etc. Internal components are omitted.

As is apparent from the figure, an angle portion 3 is continuously provided at the tip of the flexible portion 2 constituting the insertion portion 1, and a hard tip portion 4 is continuously provided at the angle portion 3. ing. In the drawings, the angle portion 3 and the hard tip portion 4 are shown in a simplified manner. The treatment instrument insertion channel 5 is divided into two parts, and the part of the flexible part 2 up to the vicinity of the connecting part to the angle part 3 is formed by the first flexible tube 6, and 1 flexible tube 6 has a second
The flexible tube 7 of is connected. The connecting portions are connected by a hard connecting pipe 8 made of metal or plastic. In addition, a treatment instrument insertion passage 9 is provided inside the distal end hard portion 4, and a hard connection pipe 10 made of metal, plastic, or the like is attached to the treatment instrument insertion passage 9, and the second flexible pipe is provided. The flexible tube 6 is connected to this connecting pipe 10. The connection structure of the first flexible tube 6 and the second flexible tube 7 should be performed by using an appropriate means other than the above, for example, directly connecting both flexible tubes. You can

Here, the first flexible tube 6 is made of, for example, a fluorocarbon resin or other polymer material. On the other hand, the second flexible tube 7 has the structure shown in FIG. That is, the second flexible tube 7 is composed of the inner layer 11 and the outer layer 12. Inner layer 1
Reference numeral 1 denotes a crystalline polymer resin, which is formed of a thin-film tube made of, for example, a fluororesin, so that when a treatment tool such as forceps is inserted thereinto, slipping can be improved. .. Further, the outer layer 12 has a function of maintaining strength such as kink resistance and shape-retaining property, and the structure is such that the net 14 as a reinforcing layer is embedded in the urethane resin layer 13 as a thermoplastic resin. It is made to enter. Here, the net 14 has a spring property such as hard stainless fiber, amorphous metal fiber, or tungsten fiber, and is formed by braiding hard metal fiber.

Thus, the net 14 has a structure for exhibiting a sufficient shape-retaining ability even when it is bent at the maximum angle in the curved portion of the insertion portion, for example, an ultrafine diameter of about 0.1 mm. The hard stainless wire made of the elemental wire is braided with 18 striking numbers and 2 holding numbers. Further, since the maximum angle angle of the angle portion 3 may have a radius of curvature of about 15 mm, the bias angle is set to about 70 to 50 ° in order to easily bend even in this case. preferable. further,
The urethane resin layer 13 in which the net 14 is embedded must have a thickness that can completely cover the net 14, and the first flexible tube 6 is curved,
A soft material is preferably used so that the net 14 does not become a resistance when it expands and contracts, and distortion or the like does not occur.

Here, the second flexible tube 7 must have flexibility as a whole, but by making the tip portion thereof, that is, the connecting portion side to the connecting pipe 10 hard to some extent, it becomes abrupt. It is necessary to protect it by preventing the hardness from changing. Moreover, it is preferable that this hardness continuously changes. For this reason, the net 14 constituting the second flexible tube 7 is spot-welded at an appropriate place so that the hardness can be changed. That is, if the intersection of the wires forming the net 14 is fixed by spot welding, the expansion and contraction of that portion is restricted, and the hardness increases. The narrower the pitch of the spot welding points, the harder it becomes.

Therefore, as indicated by symbol S in FIG. 3, welding is performed most densely at the end position of the net 14 and spot welding is performed so that the pitch interval of the welding point gradually increases to a predetermined portion. Further, in order to make the second flexible tube 7 have the same hardness in any direction, three or more welding spots S are provided at substantially equal angular intervals in the circumferential direction. Thus, spot welding not only increases hardness but also improves strength. Therefore, as a whole, the strength of the vicinity of the connecting portion of the second flexible tube 7 to the connecting pipe 10 is improved, and even if the angle portion 3 is largely curved, the angle portion 3 is combined with the upper and lower sides in both directions. Even if the second flexible tube 7 is twisted as in the case of being operated, the deformation due to this twist can be effectively absorbed between the welding spots S, and the strength is sufficiently maintained and the seat There is no risk of bending or deformation.

Here, the net 14 includes the inner layer 11 and the outer layer 1.
Since it is braided on the urethane resin layer 13 forming a part of 2, the spot welding is performed in order to ensure that it can be driven into the intersection of the wire of the net 14. It is preferable to use a laser welding means having good properties.

Note that spot welding is performed not only on the portion of the second flexible tube 7 connected to the distal end hard portion 5 but also on the side of the second flexible tube 7 connected to the first flexible tube 6. You can also do it. Further, although the treatment instrument insertion channel 5 is configured to be divided into the first movable tube 6 and the second flexible tube 7, the entire configuration may be similar to that of the second flexible tube. Good. Further, in the case where the angle portion is configured to be curved only in one of the vertical and horizontal directions, spot welding may be performed at two or more locations in the curved direction.

[0019]

As described above, according to the present invention, a portion near the end portion of the insertion portion of the net embedded in the tube made of the polymer material on the side of the connection portion to the hard tip portion is spot-welded. Therefore, when the angle portion is bent, stress is not concentrated on the connection portion to the hard tip portion, and the shape retaining ability of the portion is improved, so that deformation, kink, etc. It is prevented from occurring and becomes durable.

[Brief description of drawings]

FIG. 1 is a structural explanatory view of a distal end portion of an insertion portion of an endoscope.

FIG. 2 is a structural explanatory view of a second flexible tube.

FIG. 3 is an explanatory view showing a welded portion with respect to a net.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insertion part 2 Soft part 5 Treatment tool insertion channel 6 1st flexible tube 7 2nd flexible tube 11 Inner layer 12 Outer layer 13 Urethane layer 14 Net S S welding spot

Claims (2)

[Claims] 1. A flexible tube, which is provided so as to be positioned at least in an angle portion of an insertion portion of an endoscope, and in which a net made of a braided metal fiber is embedded in a tube made of a polymer material. A treatment instrument insertion channel for an endoscope, wherein a plurality of spot welds are configured to be formed on a portion of a net in the vicinity of an end portion of the insertion portion on the side of a connection portion to the distal end hard portion. 2. The spot welding pitch interval is configured such that the end portion on the side connected to the tip hard portion is made dense and gradually roughened from this end portion. Channel for inserting the treatment tool of the endoscope.